A:What do you usually do during the holiday?B:Lots of things,such as eating and drinking,playing majiang,going to movies and temple fairs (庙会),visiting relatives and friends and so on.In many places people like to set off firecrackers (鞭炮).It is very interesting.But now it ______in some big cities because it is not safe.
选项:
a、doesn't allow
b、isn't allowed
c、allows
d、allowed